A 54-year history of collaboration and innovation
The International Conference on Electron Spectroscopy and Structure (ICESS) has a long-standing history that spans more than five decades. Since its inaugural meeting in 1971, the conference has served as a central forum for scientists working at the intersection of spectroscopy, materials science, chemistry, and surface science.
Returning to its roots, the 2025 conference was held in Northern California—the same region as the inaugural conference in Asilomar in 1971. At that time, the electron spectroscopy field was still in its infancy. The purpose of the meeting, as defined by David A. Shirley, was to bring together colleagues with multifaceted interests in photoelectron spectroscopy and to discuss recent progress and challenges in the field.
Since then, ICESS has evolved into a globally recognized gathering for scientific exchange and community building. The Advanced Light Source (ALS) served as a co-host and co-sponsor, alongside SLAC National Accelerator Laboratory (SLAC), Brookhaven National Laboratory, Amsterdam Scientific Instruments, SIGRAY, and nine additional sponsors.
This year’s conference was organized by Eli Rotenberg, Oliver Gessner, and Slavo Nemšák. Each organizer represented a different area of spectroscopy, helping to shape a program that reflected the field’s increasing interdisciplinary nature. While emerging techniques were primarily featured in the poster sessions, the scientific program also included major research talks submitted under a general techniques category, showcasing both methodological and application-driven advances.
The development of the program and meeting required many contributors. The ICESS international advisory board of 20 experts coordinated the plenary talks. The three local organizers together with the international program committee of another 20 experts then nominated and selected invited speakers, resulting in a vast lineup of talks. The ALS Administrative Group collaborated closely with the organizers to ensure orchestration of the event on the ground–from overseeing event management to communication with attendees.
“I’m incredibly proud of the ALS admin team for the dedication and hard work that went into pulling off an event of a scale we’ve never tackled before,” shared Andrea Taylor, interim principal supervisor of the ALS Administrative Group. “In close partnership with Eli and Slavo, the team rose to the challenge with professionalism, flexibility, and attention to detail. While we certainly picked up a few lessons for next time, everything ran smoothly. I’m deeply grateful for the care and commitment each of them brought to making ICESS a success.”
Insights into the future of spectroscopy
The first day of the conference opened with several plenary talks, one by Professor Giulia Galli of the University of Chicago and Argonne National Laboratory, titled “Recent Progress in Predicting the Optical Properties of Defective and Disordered Systems.”
In her talk, Professor Galli reflected on the evolving role of theory and computation in spectroscopy.
“Scientists are now able to pair theory and practice earlier in experimentation, instead of after the experiment happens,” she said. “AI can make a difference as a tool when you can predict the next step in an experiment, and you can learn from the last step using it. That, in my opinion, will be the most spectacular success of AI.”
Attendees also had the opportunity to learn about the new and innovative research areas in the field from early career scientists during the poster sessions. The poster sessions featured topics from next-generation nanoARPES techniques to application of machine learning methods in medical imaging.
A focus on team science and early career networking
ICESS places a strong emphasis on collaboration and team science. Networking is a core mission of the conference and is supported through daily events designed to foster meaningful connections, particularly for early career scientists. The program included a welcome reception, informal gatherings, small-group meetings between early career researchers and plenary speakers, and a dedicated networking dinner.
“We hope that attendees from all over the world feel welcomed and have a positive experience at the conference,” said Eli Rotenberg, a senior scientist at the ALS and meeting co-organizer.
To promote accessibility, early career participants were offered reduced registration fees. In total, 90 early career scientists submitted abstracts , and 30 were selected to present talks. Poster presentations also formed the basis for the ESLPEC Student Awards. These awards, established by the Journal of Electron Spectroscopy and Related Phenomena, aim to support young researchers by funding their participation in relevant conferences. The awards are given annually in two categories: atomic, molecular, and optical physics, and condensed matter physics. This year, prizes were awarded to Soobin Park of Yonsei University for her work on “Electron Rotons in a Two-Dimensional Dipole Liquid,” and Alaina T. Humiston of the Illinois Institute of Technology for her work on “X-ray Photoelectron Spectroscopy and X-ray Emission Spectroscopy Data Fitting Using a Genetic Algorithm.”
“One of my first conferences abroad as a German PhD student was the ICESS meeting in Berkeley in 2000. Therefore, I was particularly excited to welcome so many students and postdocs at this year’s ICESS as a co-organizer. I hope we manage to plant some seeds for the next generation of scientists in our fields of research,” said Oliver Gessner, a senior scientist in the Chemical Sciences Division at Lawrence Berkeley National Laboratory (Berkeley Lab) and meeting co-organizer.
The hallways echoed with conversations that may lead to significant career advancements. Each day provided increasingly structured opportunities to connect, exchange ideas, and support emerging scientists.
“The lucky attendees will probably find their next job at this conference,” said Slavo Nemšák, a ALS staff scientist and co-chair of the meeting. “The next set of lucky ones will start a new collaboration at the ALS or other laboratories. Collaborations on proposals emerge right here.”
Some participants headed to the ALS for a tour led by ALS scientists and communications staff at the close of the first day. Over 35 attendees toured the ring and got to connect with techniques special to the ALS. This hands-on experience at Berkeley Lab further supported networking opportunities and served as a breeding ground for new experimentation ideas. On the last day of the conference, some participants traveled to Stanford Synchrotron Radiation Lightsource and the Linac Coherent Light Source for a tour and learned about how new advancements are reducing experimental time down to minutes.
A first international stage for many
For many attendees, ICESS 2025 was their first opportunity to present research on an international stage.
“This is my first international conference, and it’s really great to meet people from all around the world doing this work,” said Carlos Perez, a postdoctoral researcher in the Chemical Sciences Division at Berkeley Lab. “I’m hoping for a new collaboration to spark out of this time together.”
Perez gave a talk titled “Tuning Au–TiO₂ Photocatalytic Interfaces: Impact of Oxygen Vacancies and Gold Nanoparticle Size on Electronic Structure and Carrier Dynamics,” presenting results on CO₂ interfaces and density functional theory. His findings highlight the importance of defect engineering and interfacial structural dynamics in tuning the performance of Au–TiO₂ photocatalysts.
Rotenberg reflected on how the conference serves as a platform for building lasting memories and establishing one’s place in the field. “The first time I attended a big international conference, I felt a great sense of pride and belonging—that you’re part of this community. And you meet famous people from the other side of the planet, and they comment on how great your talk was.” He emphasized how such moments can shift a researcher’s mindset and motivate their life’s work.
This conference was made possible by the generous support from ALS, SLAC and Brookhaven National Laboratories, whose contributions were instrumental in the success of this event. The week-long program was further supported by the ALS administrative and business management groups, LBNL Conference Services group, the organizers, the international program committee, and the ICESS international board.
